Sofia Lejonvarn
She/Her
Product designer focused on the intersection of sports innovation, mechanics and user-centred design, with experience translating complex performance data into accessible physical products.
She/Her
A Customisable Tennis Racquet Performance Testing System
SpecX is a customisable tennis racquet performance testing system that helps players physically experience how racquet specifications affect feel and performance. Through interchangeable weighted tuning, users can test industry-average racquet specifications and explore customisation before purchasing.
Many players struggle to understand how racquet specifications affect performance, often relying on expensive demo racquets or trial-and-error purchasing. Commercial racquets offer fixed configurations, making meaningful comparison difficult. SpecX was developed to make racquet testing more accessible, allowing players to physically compare racquet feel before investing in a purchase.
SpecX helps players physically experience how racquet specifications influence performance through interchangeable weighted tuning. Developed from the analysis of 107 adult performance racquets across Wilson, Head, Babolat and Yonex, the system allows users to test representative racquet specifications without purchasing multiple demo racquets.
Through guided Performance Scale Levels and Tuning Setups, users can compare racquet feel on court while learning how customisation affects power, control, feel and spin potential. This creates an accessible way to understand racquet performance before committing to a purchase or permanent lead tape modifications.
SpecX was designed to make racquet experimentation intuitive and repeatable. Modular weighted inserts allow users to fine-tune performance characteristics through controlled placement around the frame. The visual design communicates adjustment zones clearly while maintaining the familiar language of a performance tennis racquet.
User testing explored how players interacted with interchangeable weighting and whether physical experimentation improved understanding of racquet feel. Testing sessions informed refinements to usability, weight positioning and tuning clarity.
A turntable concept inspired by the iconic forms and materials of electric guitars, combining retro vinyl listening with modern functionality. The project explored CMF, product form development and contemporary home audio aesthetics.
A remotely controlled rescue robot developed for obstacle navigation and fire extinguishing, combining CAD, prototyping, electronics integration and mechanism design.